Vehicles often use air-extractors to influence air flow from a vehicle passenger compartment to enhance passenger comfort and to prevent window fogging. As a climate control system takes in ambient air from outside the vehicle, air exhaustion through the extractors provides for proper circulation and can reduce pressure from building up in the compartment. When a vehicle door is closed, pressure can suddenly rise within the compartment which can result in a high closing effort. Vehicle door closing effort is an important attribute for user satisfaction. If it is too difficult to close a vehicle door, a passenger may become frustrated due to time consuming efforts to close the door when entering and exiting the vehicle.
As door closure effort is directly tied to the in-vehicle air flow rate, it is often difficult to achieve required flow rates to deliver good performance with traditional extractors due to packaging constraints. Typically, two to four air extractors are packaged in a rear portion of the vehicle to deliver the desired flow attributes. Larger air extractor openings allow for adequate air flow but can result in an increase in noise, vibration, and harshness (NVH) performance, which is not desirable. Some NVH solutions use springs to close air extractor flaps until a certain cabin pressure is reached; however, this operation is contrary to climate fogging and door closing efforts. Further, using larger air extractors is also not desired due to packaging constraints.